"NEOGAL is an intensive, coordinated effort to explore uncharted territory in the early chemical evolution of galaxies through the development of an innovative set of spectral analysis tools. This will be achieved through the accomplishment of four interdisciplinary projects using state-of-the-art techniques:1. The development of a new approach overcoming the limitations of existing methods, to measure the chemical composition of ionized gas with unknown heavy element abundance ratios in high-redshift galaxies;2. The combination of this approach with sophisticated models of the ultraviolet emission from young stellar populations, to allow differentiated constraints on the chemical composition of stars and gas;3. The combination of these models with cosmological simulations of galaxy formation, to identify the spectral signatures of competing scenarios of early chemical evolution in observations of statistical samples of high-redshift galaxies;4. The development of an integrated web service to allow the astronomical community at large to exploit these models to interpret observations of distant galaxies.The spectral analysis tools developed in the framework of this project will open powerful new opportunities to probe the early star formation and chemical enrichment histories of galaxies. Moreover, by allowing the consistent interpretation of stellar and nebular emission, these tools will provide valuable constraints on parameters such as the escape fraction of ionizing photons and hence the contribution by galaxies to the ionizing background. These models therefore should have a profound impact on the optimal design of future surveys of primeval galaxies that will be carried out with the next generation of large facilities, such as the James Webb Space Telescope and the European Extremely Large Telescope."